The Shimano CN-M910 Chain Quick Link provides flexibility and speed. It is designed with tool-free assembly in mind for quick on-the-trail repairs meaning less bulk in your saddlebag and more time on the bike. There is a professional assembly tool available for the rapid repair of multiple chains. Its made for 12-speed chains and is compatible with all Shimano 12 speed chains. It is not compatible with current HG-X11 chains. It is Nickel plated for durability and rust prevention.